class_docstr: Trident roi head.
  
  Args:
      num_branch (int): Number of branches in TridentNet.
      test_branch_idx (int): In inference, all 3 branches will be used
          if `test_branch_idx==-1`, otherwise only branch with index
          `test_branch_idx` will be used.
code: def __init__(self, num_branch, test_branch_idx, **kwargs):
      self.num_branch = num_branch
      self.test_branch_idx = test_branch_idx
      super(TridentRoIHead, self).__init__(**kwargs)
  
file_path: insightface/detection/scrfd/mmdet/models/roi_heads/trident_roi_head.py
imports: import torch
  from mmcv.ops import batched_nms
  from mmdet.core import bbox2result, bbox2roi, bbox_mapping, merge_aug_bboxes, multiclass_nms
  from mmdet.models.roi_heads.standard_roi_head import StandardRoIHead
  from ..builder import HEADS
label_desc: Use image node_id 1 to create a new TridentRoIHead object from inherited base classes: StandardRoIHead with example: obj = TridentRoIHead(num_branch, test_branch_idx)